1/*
2 * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank
3 * Copyright (c) 1995 Martin Husemann
4 * Some structure declaration borrowed from Paul Popelka
5 * (paulp@uts.amdahl.com), see /sys/msdosfs/ for reference.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28
29#include <sys/cdefs.h>
30#ifndef lint
31__RCSID("$NetBSD: dir.c,v 1.20 2006/06/05 16:51:18 christos Exp $");
32static const char rcsid[] =
33  "$FreeBSD$";
34#endif /* not lint */
35
36#include <stdio.h>
37#include <stdlib.h>
38#include <string.h>
39#include <ctype.h>
40#include <unistd.h>
41#include <time.h>
42
43#include <sys/param.h>
44
45#include "ext.h"
46#include "fsutil.h"
47
48#define	SLOT_EMPTY	0x00		/* slot has never been used */
49#define	SLOT_E5		0x05		/* the real value is 0xe5 */
50#define	SLOT_DELETED	0xe5		/* file in this slot deleted */
51
52#define	ATTR_NORMAL	0x00		/* normal file */
53#define	ATTR_READONLY	0x01		/* file is readonly */
54#define	ATTR_HIDDEN	0x02		/* file is hidden */
55#define	ATTR_SYSTEM	0x04		/* file is a system file */
56#define	ATTR_VOLUME	0x08		/* entry is a volume label */
57#define	ATTR_DIRECTORY	0x10		/* entry is a directory name */
58#define	ATTR_ARCHIVE	0x20		/* file is new or modified */
59
60#define	ATTR_WIN95	0x0f		/* long name record */
61
62/*
63 * This is the format of the contents of the deTime field in the direntry
64 * structure.
65 * We don't use bitfields because we don't know how compilers for
66 * arbitrary machines will lay them out.
67 */
68#define DT_2SECONDS_MASK	0x1F	/* seconds divided by 2 */
69#define DT_2SECONDS_SHIFT	0
70#define DT_MINUTES_MASK		0x7E0	/* minutes */
71#define DT_MINUTES_SHIFT	5
72#define DT_HOURS_MASK		0xF800	/* hours */
73#define DT_HOURS_SHIFT		11
74
75/*
76 * This is the format of the contents of the deDate field in the direntry
77 * structure.
78 */
79#define DD_DAY_MASK		0x1F	/* day of month */
80#define DD_DAY_SHIFT		0
81#define DD_MONTH_MASK		0x1E0	/* month */
82#define DD_MONTH_SHIFT		5
83#define DD_YEAR_MASK		0xFE00	/* year - 1980 */
84#define DD_YEAR_SHIFT		9
85
86
87/* dir.c */
88static struct dosDirEntry *newDosDirEntry(void);
89static void freeDosDirEntry(struct dosDirEntry *);
90static struct dirTodoNode *newDirTodo(void);
91static void freeDirTodo(struct dirTodoNode *);
92static char *fullpath(struct dosDirEntry *);
93static u_char calcShortSum(u_char *);
94static int delete(int, struct bootblock *, struct fatEntry *, cl_t, int,
95    cl_t, int, int);
96static int removede(int, struct bootblock *, struct fatEntry *, u_char *,
97    u_char *, cl_t, cl_t, cl_t, char *, int);
98static int checksize(struct bootblock *, struct fatEntry *, u_char *,
99    struct dosDirEntry *);
100static int readDosDirSection(int, struct bootblock *, struct fatEntry *,
101    struct dosDirEntry *);
102
103/*
104 * Manage free dosDirEntry structures.
105 */
106static struct dosDirEntry *freede;
107
108static struct dosDirEntry *
109newDosDirEntry(void)
110{
111	struct dosDirEntry *de;
112
113	if (!(de = freede)) {
114		if (!(de = (struct dosDirEntry *)malloc(sizeof *de)))
115			return 0;
116	} else
117		freede = de->next;
118	return de;
119}
120
121static void
122freeDosDirEntry(struct dosDirEntry *de)
123{
124	de->next = freede;
125	freede = de;
126}
127
128/*
129 * The same for dirTodoNode structures.
130 */
131static struct dirTodoNode *freedt;
132
133static struct dirTodoNode *
134newDirTodo(void)
135{
136	struct dirTodoNode *dt;
137
138	if (!(dt = freedt)) {
139		if (!(dt = (struct dirTodoNode *)malloc(sizeof *dt)))
140			return 0;
141	} else
142		freedt = dt->next;
143	return dt;
144}
145
146static void
147freeDirTodo(struct dirTodoNode *dt)
148{
149	dt->next = freedt;
150	freedt = dt;
151}
152
153/*
154 * The stack of unread directories
155 */
156static struct dirTodoNode *pendingDirectories = NULL;
157
158/*
159 * Return the full pathname for a directory entry.
160 */
161static char *
162fullpath(struct dosDirEntry *dir)
163{
164	static char namebuf[MAXPATHLEN + 1];
165	char *cp, *np;
166	int nl;
167
168	cp = namebuf + sizeof namebuf - 1;
169	*cp = '\0';
170	do {
171		np = dir->lname[0] ? dir->lname : dir->name;
172		nl = strlen(np);
173		if ((cp -= nl) <= namebuf + 1)
174			break;
175		memcpy(cp, np, nl);
176		*--cp = '/';
177	} while ((dir = dir->parent) != NULL);
178	if (dir)
179		*--cp = '?';
180	else
181		cp++;
182	return cp;
183}
184
185/*
186 * Calculate a checksum over an 8.3 alias name
187 */
188static u_char
189calcShortSum(u_char *p)
190{
191	u_char sum = 0;
192	int i;
193
194	for (i = 0; i < 11; i++) {
195		sum = (sum << 7)|(sum >> 1);	/* rotate right */
196		sum += p[i];
197	}
198
199	return sum;
200}
201
202/*
203 * Global variables temporarily used during a directory scan
204 */
205static char longName[DOSLONGNAMELEN] = "";
206static u_char *buffer = NULL;
207static u_char *delbuf = NULL;
208
209struct dosDirEntry *rootDir;
210static struct dosDirEntry *lostDir;
211
212/*
213 * Init internal state for a new directory scan.
214 */
215int
216resetDosDirSection(struct bootblock *boot, struct fatEntry *fat)
217{
218	int b1, b2;
219	cl_t cl;
220	int ret = FSOK;
221	size_t len;
222
223	b1 = boot->bpbRootDirEnts * 32;
224	b2 = boot->bpbSecPerClust * boot->bpbBytesPerSec;
225
226	if ((buffer = malloc(len = b1 > b2 ? b1 : b2)) == NULL) {
227		perr("No space for directory buffer (%zu)", len);
228		return FSFATAL;
229	}
230
231	if ((delbuf = malloc(len = b2)) == NULL) {
232		free(buffer);
233		perr("No space for directory delbuf (%zu)", len);
234		return FSFATAL;
235	}
236
237	if ((rootDir = newDosDirEntry()) == NULL) {
238		free(buffer);
239		free(delbuf);
240		perr("No space for directory entry");
241		return FSFATAL;
242	}
243
244	memset(rootDir, 0, sizeof *rootDir);
245	if (boot->flags & FAT32) {
246		if (boot->bpbRootClust < CLUST_FIRST ||
247		    boot->bpbRootClust >= boot->NumClusters) {
248			pfatal("Root directory starts with cluster out of range(%u)",
249			       boot->bpbRootClust);
250			return FSFATAL;
251		}
252		cl = fat[boot->bpbRootClust].next;
253		if (cl < CLUST_FIRST
254		    || (cl >= CLUST_RSRVD && cl< CLUST_EOFS)
255		    || fat[boot->bpbRootClust].head != boot->bpbRootClust) {
256			if (cl == CLUST_FREE)
257				pwarn("Root directory starts with free cluster\n");
258			else if (cl >= CLUST_RSRVD)
259				pwarn("Root directory starts with cluster marked %s\n",
260				      rsrvdcltype(cl));
261			else {
262				pfatal("Root directory doesn't start a cluster chain");
263				return FSFATAL;
264			}
265			if (ask(1, "Fix")) {
266				fat[boot->bpbRootClust].next = CLUST_FREE;
267				ret = FSFATMOD;
268			} else
269				ret = FSFATAL;
270		}
271
272		fat[boot->bpbRootClust].flags |= FAT_USED;
273		rootDir->head = boot->bpbRootClust;
274	}
275
276	return ret;
277}
278
279/*
280 * Cleanup after a directory scan
281 */
282void
283finishDosDirSection(void)
284{
285	struct dirTodoNode *p, *np;
286	struct dosDirEntry *d, *nd;
287
288	for (p = pendingDirectories; p; p = np) {
289		np = p->next;
290		freeDirTodo(p);
291	}
292	pendingDirectories = 0;
293	for (d = rootDir; d; d = nd) {
294		if ((nd = d->child) != NULL) {
295			d->child = 0;
296			continue;
297		}
298		if (!(nd = d->next))
299			nd = d->parent;
300		freeDosDirEntry(d);
301	}
302	rootDir = lostDir = NULL;
303	free(buffer);
304	free(delbuf);
305	buffer = NULL;
306	delbuf = NULL;
307}
308
309/*
310 * Delete directory entries between startcl, startoff and endcl, endoff.
311 */
312static int
313delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
314    int startoff, cl_t endcl, int endoff, int notlast)
315{
316	u_char *s, *e;
317	off_t off;
318	int clsz = boot->bpbSecPerClust * boot->bpbBytesPerSec;
319
320	s = delbuf + startoff;
321	e = delbuf + clsz;
322	while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
323		if (startcl == endcl) {
324			if (notlast)
325				break;
326			e = delbuf + endoff;
327		}
328		off = startcl * boot->bpbSecPerClust + boot->ClusterOffset;
329		off *= boot->bpbBytesPerSec;
330		if (lseek(f, off, SEEK_SET) != off
331		    || read(f, delbuf, clsz) != clsz) {
332			perr("Unable to read directory");
333			return FSFATAL;
334		}
335		while (s < e) {
336			*s = SLOT_DELETED;
337			s += 32;
338		}
339		if (lseek(f, off, SEEK_SET) != off
340		    || write(f, delbuf, clsz) != clsz) {
341			perr("Unable to write directory");
342			return FSFATAL;
343		}
344		if (startcl == endcl)
345			break;
346		startcl = fat[startcl].next;
347		s = delbuf;
348	}
349	return FSOK;
350}
351
352static int
353removede(int f, struct bootblock *boot, struct fatEntry *fat, u_char *start,
354    u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, char *path, int type)
355{
356	switch (type) {
357	case 0:
358		pwarn("Invalid long filename entry for %s\n", path);
359		break;
360	case 1:
361		pwarn("Invalid long filename entry at end of directory %s\n",
362		    path);
363		break;
364	case 2:
365		pwarn("Invalid long filename entry for volume label\n");
366		break;
367	}
368	if (ask(0, "Remove")) {
369		if (startcl != curcl) {
370			if (delete(f, boot, fat,
371				   startcl, start - buffer,
372				   endcl, end - buffer,
373				   endcl == curcl) == FSFATAL)
374				return FSFATAL;
375			start = buffer;
376		}
377		/* startcl is < CLUST_FIRST for !fat32 root */
378		if ((endcl == curcl) || (startcl < CLUST_FIRST))
379			for (; start < end; start += 32)
380				*start = SLOT_DELETED;
381		return FSDIRMOD;
382	}
383	return FSERROR;
384}
385
386/*
387 * Check an in-memory file entry
388 */
389static int
390checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
391    struct dosDirEntry *dir)
392{
393	/*
394	 * Check size on ordinary files
395	 */
396	u_int32_t physicalSize;
397
398	if (dir->head == CLUST_FREE)
399		physicalSize = 0;
400	else {
401		if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
402			return FSERROR;
403		physicalSize = fat[dir->head].length * boot->ClusterSize;
404	}
405	if (physicalSize < dir->size) {
406		pwarn("size of %s is %u, should at most be %u\n",
407		      fullpath(dir), dir->size, physicalSize);
408		if (ask(1, "Truncate")) {
409			dir->size = physicalSize;
410			p[28] = (u_char)physicalSize;
411			p[29] = (u_char)(physicalSize >> 8);
412			p[30] = (u_char)(physicalSize >> 16);
413			p[31] = (u_char)(physicalSize >> 24);
414			return FSDIRMOD;
415		} else
416			return FSERROR;
417	} else if (physicalSize - dir->size >= boot->ClusterSize) {
418		pwarn("%s has too many clusters allocated\n",
419		      fullpath(dir));
420		if (ask(1, "Drop superfluous clusters")) {
421			cl_t cl;
422			u_int32_t sz, len;
423
424			for (cl = dir->head, len = sz = 0;
425			    (sz += boot->ClusterSize) < dir->size; len++)
426				cl = fat[cl].next;
427			clearchain(boot, fat, fat[cl].next);
428			fat[cl].next = CLUST_EOF;
429			fat[dir->head].length = len;
430			return FSFATMOD;
431		} else
432			return FSERROR;
433	}
434	return FSOK;
435}
436
437/*
438 * Read a directory and
439 *   - resolve long name records
440 *   - enter file and directory records into the parent's list
441 *   - push directories onto the todo-stack
442 */
443static int
444readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
445    struct dosDirEntry *dir)
446{
447	struct dosDirEntry dirent, *d;
448	u_char *p, *vallfn, *invlfn, *empty;
449	off_t off;
450	int i, j, k, last;
451	cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
452	char *t;
453	u_int lidx = 0;
454	int shortSum;
455	int mod = FSOK;
456#define	THISMOD	0x8000			/* Only used within this routine */
457
458	cl = dir->head;
459	if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
460		/*
461		 * Already handled somewhere else.
462		 */
463		return FSOK;
464	}
465	shortSum = -1;
466	vallfn = invlfn = empty = NULL;
467	do {
468		if (!(boot->flags & FAT32) && !dir->parent) {
469			last = boot->bpbRootDirEnts * 32;
470			off = boot->bpbResSectors + boot->bpbFATs *
471			    boot->FATsecs;
472		} else {
473			last = boot->bpbSecPerClust * boot->bpbBytesPerSec;
474			off = cl * boot->bpbSecPerClust + boot->ClusterOffset;
475		}
476
477		off *= boot->bpbBytesPerSec;
478		if (lseek(f, off, SEEK_SET) != off
479		    || read(f, buffer, last) != last) {
480			perr("Unable to read directory");
481			return FSFATAL;
482		}
483		last /= 32;
484		/*
485		 * Check `.' and `..' entries here?			XXX
486		 */
487		for (p = buffer, i = 0; i < last; i++, p += 32) {
488			if (dir->fsckflags & DIREMPWARN) {
489				*p = SLOT_EMPTY;
490				continue;
491			}
492
493			if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
494				if (*p == SLOT_EMPTY) {
495					dir->fsckflags |= DIREMPTY;
496					empty = p;
497					empcl = cl;
498				}
499				continue;
500			}
501
502			if (dir->fsckflags & DIREMPTY) {
503				if (!(dir->fsckflags & DIREMPWARN)) {
504					pwarn("%s has entries after end of directory\n",
505					      fullpath(dir));
506					if (ask(1, "Extend")) {
507						u_char *q;
508
509						dir->fsckflags &= ~DIREMPTY;
510						if (delete(f, boot, fat,
511							   empcl, empty - buffer,
512							   cl, p - buffer, 1) == FSFATAL)
513							return FSFATAL;
514						q = empcl == cl ? empty : buffer;
515						for (; q < p; q += 32)
516							*q = SLOT_DELETED;
517						mod |= THISMOD|FSDIRMOD;
518					} else if (ask(0, "Truncate"))
519						dir->fsckflags |= DIREMPWARN;
520				}
521				if (dir->fsckflags & DIREMPWARN) {
522					*p = SLOT_DELETED;
523					mod |= THISMOD|FSDIRMOD;
524					continue;
525				} else if (dir->fsckflags & DIREMPTY)
526					mod |= FSERROR;
527				empty = NULL;
528			}
529
530			if (p[11] == ATTR_WIN95) {
531				if (*p & LRFIRST) {
532					if (shortSum != -1) {
533						if (!invlfn) {
534							invlfn = vallfn;
535							invcl = valcl;
536						}
537					}
538					memset(longName, 0, sizeof longName);
539					shortSum = p[13];
540					vallfn = p;
541					valcl = cl;
542				} else if (shortSum != p[13]
543					   || lidx != (*p & LRNOMASK)) {
544					if (!invlfn) {
545						invlfn = vallfn;
546						invcl = valcl;
547					}
548					if (!invlfn) {
549						invlfn = p;
550						invcl = cl;
551					}
552					vallfn = NULL;
553				}
554				lidx = *p & LRNOMASK;
555				t = longName + --lidx * 13;
556				for (k = 1; k < 11 && t < longName +
557				    sizeof(longName); k += 2) {
558					if (!p[k] && !p[k + 1])
559						break;
560					*t++ = p[k];
561					/*
562					 * Warn about those unusable chars in msdosfs here?	XXX
563					 */
564					if (p[k + 1])
565						t[-1] = '?';
566				}
567				if (k >= 11)
568					for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) {
569						if (!p[k] && !p[k + 1])
570							break;
571						*t++ = p[k];
572						if (p[k + 1])
573							t[-1] = '?';
574					}
575				if (k >= 26)
576					for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) {
577						if (!p[k] && !p[k + 1])
578							break;
579						*t++ = p[k];
580						if (p[k + 1])
581							t[-1] = '?';
582					}
583				if (t >= longName + sizeof(longName)) {
584					pwarn("long filename too long\n");
585					if (!invlfn) {
586						invlfn = vallfn;
587						invcl = valcl;
588					}
589					vallfn = NULL;
590				}
591				if (p[26] | (p[27] << 8)) {
592					pwarn("long filename record cluster start != 0\n");
593					if (!invlfn) {
594						invlfn = vallfn;
595						invcl = cl;
596					}
597					vallfn = NULL;
598				}
599				continue;	/* long records don't carry further
600						 * information */
601			}
602
603			/*
604			 * This is a standard msdosfs directory entry.
605			 */
606			memset(&dirent, 0, sizeof dirent);
607
608			/*
609			 * it's a short name record, but we need to know
610			 * more, so get the flags first.
611			 */
612			dirent.flags = p[11];
613
614			/*
615			 * Translate from 850 to ISO here		XXX
616			 */
617			for (j = 0; j < 8; j++)
618				dirent.name[j] = p[j];
619			dirent.name[8] = '\0';
620			for (k = 7; k >= 0 && dirent.name[k] == ' '; k--)
621				dirent.name[k] = '\0';
622			if (dirent.name[k] != '\0')
623				k++;
624			if (dirent.name[0] == SLOT_E5)
625				dirent.name[0] = 0xe5;
626
627			if (dirent.flags & ATTR_VOLUME) {
628				if (vallfn || invlfn) {
629					mod |= removede(f, boot, fat,
630							invlfn ? invlfn : vallfn, p,
631							invlfn ? invcl : valcl, -1, 0,
632							fullpath(dir), 2);
633					vallfn = NULL;
634					invlfn = NULL;
635				}
636				continue;
637			}
638
639			if (p[8] != ' ')
640				dirent.name[k++] = '.';
641			for (j = 0; j < 3; j++)
642				dirent.name[k++] = p[j+8];
643			dirent.name[k] = '\0';
644			for (k--; k >= 0 && dirent.name[k] == ' '; k--)
645				dirent.name[k] = '\0';
646
647			if (vallfn && shortSum != calcShortSum(p)) {
648				if (!invlfn) {
649					invlfn = vallfn;
650					invcl = valcl;
651				}
652				vallfn = NULL;
653			}
654			dirent.head = p[26] | (p[27] << 8);
655			if (boot->ClustMask == CLUST32_MASK)
656				dirent.head |= (p[20] << 16) | (p[21] << 24);
657			dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24);
658			if (vallfn) {
659				strlcpy(dirent.lname, longName,
660				    sizeof(dirent.lname));
661				longName[0] = '\0';
662				shortSum = -1;
663			}
664
665			dirent.parent = dir;
666			dirent.next = dir->child;
667
668			if (invlfn) {
669				mod |= k = removede(f, boot, fat,
670						    invlfn, vallfn ? vallfn : p,
671						    invcl, vallfn ? valcl : cl, cl,
672						    fullpath(&dirent), 0);
673				if (mod & FSFATAL)
674					return FSFATAL;
675				if (vallfn
676				    ? (valcl == cl && vallfn != buffer)
677				    : p != buffer)
678					if (k & FSDIRMOD)
679						mod |= THISMOD;
680			}
681
682			vallfn = NULL; /* not used any longer */
683			invlfn = NULL;
684
685			if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
686				if (dirent.head != 0) {
687					pwarn("%s has clusters, but size 0\n",
688					      fullpath(&dirent));
689					if (ask(1, "Drop allocated clusters")) {
690						p[26] = p[27] = 0;
691						if (boot->ClustMask == CLUST32_MASK)
692							p[20] = p[21] = 0;
693						clearchain(boot, fat, dirent.head);
694						dirent.head = 0;
695						mod |= THISMOD|FSDIRMOD|FSFATMOD;
696					} else
697						mod |= FSERROR;
698				}
699			} else if (dirent.head == 0
700				   && !strcmp(dirent.name, "..")
701				   && dir->parent			/* XXX */
702				   && !dir->parent->parent) {
703				/*
704				 *  Do nothing, the parent is the root
705				 */
706			} else if (dirent.head < CLUST_FIRST
707				   || dirent.head >= boot->NumClusters
708				   || fat[dirent.head].next == CLUST_FREE
709				   || (fat[dirent.head].next >= CLUST_RSRVD
710				       && fat[dirent.head].next < CLUST_EOFS)
711				   || fat[dirent.head].head != dirent.head) {
712				if (dirent.head == 0)
713					pwarn("%s has no clusters\n",
714					      fullpath(&dirent));
715				else if (dirent.head < CLUST_FIRST
716					 || dirent.head >= boot->NumClusters)
717					pwarn("%s starts with cluster out of range(%u)\n",
718					      fullpath(&dirent),
719					      dirent.head);
720				else if (fat[dirent.head].next == CLUST_FREE)
721					pwarn("%s starts with free cluster\n",
722					      fullpath(&dirent));
723				else if (fat[dirent.head].next >= CLUST_RSRVD)
724					pwarn("%s starts with cluster marked %s\n",
725					      fullpath(&dirent),
726					      rsrvdcltype(fat[dirent.head].next));
727				else
728					pwarn("%s doesn't start a cluster chain\n",
729					      fullpath(&dirent));
730				if (dirent.flags & ATTR_DIRECTORY) {
731					if (ask(0, "Remove")) {
732						*p = SLOT_DELETED;
733						mod |= THISMOD|FSDIRMOD;
734					} else
735						mod |= FSERROR;
736					continue;
737				} else {
738					if (ask(1, "Truncate")) {
739						p[28] = p[29] = p[30] = p[31] = 0;
740						p[26] = p[27] = 0;
741						if (boot->ClustMask == CLUST32_MASK)
742							p[20] = p[21] = 0;
743						dirent.size = 0;
744						mod |= THISMOD|FSDIRMOD;
745					} else
746						mod |= FSERROR;
747				}
748			}
749
750			if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
751				fat[dirent.head].flags |= FAT_USED;
752
753			if (dirent.flags & ATTR_DIRECTORY) {
754				/*
755				 * gather more info for directories
756				 */
757				struct dirTodoNode *n;
758
759				if (dirent.size) {
760					pwarn("Directory %s has size != 0\n",
761					      fullpath(&dirent));
762					if (ask(1, "Correct")) {
763						p[28] = p[29] = p[30] = p[31] = 0;
764						dirent.size = 0;
765						mod |= THISMOD|FSDIRMOD;
766					} else
767						mod |= FSERROR;
768				}
769				/*
770				 * handle `.' and `..' specially
771				 */
772				if (strcmp(dirent.name, ".") == 0) {
773					if (dirent.head != dir->head) {
774						pwarn("`.' entry in %s has incorrect start cluster\n",
775						      fullpath(dir));
776						if (ask(1, "Correct")) {
777							dirent.head = dir->head;
778							p[26] = (u_char)dirent.head;
779							p[27] = (u_char)(dirent.head >> 8);
780							if (boot->ClustMask == CLUST32_MASK) {
781								p[20] = (u_char)(dirent.head >> 16);
782								p[21] = (u_char)(dirent.head >> 24);
783							}
784							mod |= THISMOD|FSDIRMOD;
785						} else
786							mod |= FSERROR;
787					}
788					continue;
789				}
790				if (strcmp(dirent.name, "..") == 0) {
791					if (dir->parent) {		/* XXX */
792						if (!dir->parent->parent) {
793							if (dirent.head) {
794								pwarn("`..' entry in %s has non-zero start cluster\n",
795								      fullpath(dir));
796								if (ask(1, "Correct")) {
797									dirent.head = 0;
798									p[26] = p[27] = 0;
799									if (boot->ClustMask == CLUST32_MASK)
800										p[20] = p[21] = 0;
801									mod |= THISMOD|FSDIRMOD;
802								} else
803									mod |= FSERROR;
804							}
805						} else if (dirent.head != dir->parent->head) {
806							pwarn("`..' entry in %s has incorrect start cluster\n",
807							      fullpath(dir));
808							if (ask(1, "Correct")) {
809								dirent.head = dir->parent->head;
810								p[26] = (u_char)dirent.head;
811								p[27] = (u_char)(dirent.head >> 8);
812								if (boot->ClustMask == CLUST32_MASK) {
813									p[20] = (u_char)(dirent.head >> 16);
814									p[21] = (u_char)(dirent.head >> 24);
815								}
816								mod |= THISMOD|FSDIRMOD;
817							} else
818								mod |= FSERROR;
819						}
820					}
821					continue;
822				}
823
824				/* create directory tree node */
825				if (!(d = newDosDirEntry())) {
826					perr("No space for directory");
827					return FSFATAL;
828				}
829				memcpy(d, &dirent, sizeof(struct dosDirEntry));
830				/* link it into the tree */
831				dir->child = d;
832
833				/* Enter this directory into the todo list */
834				if (!(n = newDirTodo())) {
835					perr("No space for todo list");
836					return FSFATAL;
837				}
838				n->next = pendingDirectories;
839				n->dir = d;
840				pendingDirectories = n;
841			} else {
842				mod |= k = checksize(boot, fat, p, &dirent);
843				if (k & FSDIRMOD)
844					mod |= THISMOD;
845			}
846			boot->NumFiles++;
847		}
848
849		if (!(boot->flags & FAT32) && !dir->parent)
850			break;
851
852		if (mod & THISMOD) {
853			last *= 32;
854			if (lseek(f, off, SEEK_SET) != off
855			    || write(f, buffer, last) != last) {
856				perr("Unable to write directory");
857				return FSFATAL;
858			}
859			mod &= ~THISMOD;
860		}
861	} while ((cl = fat[cl].next) >= CLUST_FIRST && cl < boot->NumClusters);
862	if (invlfn || vallfn)
863		mod |= removede(f, boot, fat,
864				invlfn ? invlfn : vallfn, p,
865				invlfn ? invcl : valcl, -1, 0,
866				fullpath(dir), 1);
867
868	/* The root directory of non fat32 filesystems is in a special
869	 * area and may have been modified above without being written out.
870	 */
871	if ((mod & FSDIRMOD) && !(boot->flags & FAT32) && !dir->parent) {
872		last *= 32;
873		if (lseek(f, off, SEEK_SET) != off
874		    || write(f, buffer, last) != last) {
875			perr("Unable to write directory");
876			return FSFATAL;
877		}
878		mod &= ~THISMOD;
879	}
880	return mod & ~THISMOD;
881}
882
883int
884handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
885{
886	int mod;
887
888	mod = readDosDirSection(dosfs, boot, fat, rootDir);
889	if (mod & FSFATAL)
890		return FSFATAL;
891
892	/*
893	 * process the directory todo list
894	 */
895	while (pendingDirectories) {
896		struct dosDirEntry *dir = pendingDirectories->dir;
897		struct dirTodoNode *n = pendingDirectories->next;
898
899		/*
900		 * remove TODO entry now, the list might change during
901		 * directory reads
902		 */
903		freeDirTodo(pendingDirectories);
904		pendingDirectories = n;
905
906		/*
907		 * handle subdirectory
908		 */
909		mod |= readDosDirSection(dosfs, boot, fat, dir);
910		if (mod & FSFATAL)
911			return FSFATAL;
912	}
913
914	return mod;
915}
916
917/*
918 * Try to reconnect a FAT chain into dir
919 */
920static u_char *lfbuf;
921static cl_t lfcl;
922static off_t lfoff;
923
924int
925reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
926{
927	struct dosDirEntry d;
928	u_char *p;
929
930	if (!ask(1, "Reconnect"))
931		return FSERROR;
932
933	if (!lostDir) {
934		for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
935			if (!strcmp(lostDir->name, LOSTDIR))
936				break;
937		}
938		if (!lostDir) {		/* Create LOSTDIR?		XXX */
939			pwarn("No %s directory\n", LOSTDIR);
940			return FSERROR;
941		}
942	}
943	if (!lfbuf) {
944		lfbuf = malloc(boot->ClusterSize);
945		if (!lfbuf) {
946			perr("No space for buffer");
947			return FSFATAL;
948		}
949		p = NULL;
950	} else
951		p = lfbuf;
952	while (1) {
953		if (p)
954			for (; p < lfbuf + boot->ClusterSize; p += 32)
955				if (*p == SLOT_EMPTY
956				    || *p == SLOT_DELETED)
957					break;
958		if (p && p < lfbuf + boot->ClusterSize)
959			break;
960		lfcl = p ? fat[lfcl].next : lostDir->head;
961		if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) {
962			/* Extend LOSTDIR?				XXX */
963			pwarn("No space in %s\n", LOSTDIR);
964			return FSERROR;
965		}
966		lfoff = lfcl * boot->ClusterSize
967		    + boot->ClusterOffset * boot->bpbBytesPerSec;
968		if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
969		    || (size_t)read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
970			perr("could not read LOST.DIR");
971			return FSFATAL;
972		}
973		p = lfbuf;
974	}
975
976	boot->NumFiles++;
977	/* Ensure uniqueness of entry here!				XXX */
978	memset(&d, 0, sizeof d);
979	(void)snprintf(d.name, sizeof(d.name), "%u", head);
980	d.flags = 0;
981	d.head = head;
982	d.size = fat[head].length * boot->ClusterSize;
983
984	memset(p, 0, 32);
985	memset(p, ' ', 11);
986	memcpy(p, d.name, strlen(d.name));
987	p[26] = (u_char)d.head;
988	p[27] = (u_char)(d.head >> 8);
989	if (boot->ClustMask == CLUST32_MASK) {
990		p[20] = (u_char)(d.head >> 16);
991		p[21] = (u_char)(d.head >> 24);
992	}
993	p[28] = (u_char)d.size;
994	p[29] = (u_char)(d.size >> 8);
995	p[30] = (u_char)(d.size >> 16);
996	p[31] = (u_char)(d.size >> 24);
997	fat[head].flags |= FAT_USED;
998	if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
999	    || (size_t)write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
1000		perr("could not write LOST.DIR");
1001		return FSFATAL;
1002	}
1003	return FSDIRMOD;
1004}
1005
1006void
1007finishlf(void)
1008{
1009	if (lfbuf)
1010		free(lfbuf);
1011	lfbuf = NULL;
1012}
1013